Various monitoring systems for batteries exist. For example, battery management systems may be configured to manage a battery (cell or battery pack), such as by monitoring the battery state, calculating and reporting secondary data, protecting the battery, controlling the battery's environment, and/or balancing the charge/discharge of the battery. Some battery management systems may monitor the state of the battery as represented by various parameters, including, but not limited to, voltage (e.g. total voltage, voltage of periodic taps or voltages of individual cells), temperature (e.g. average temperature, coolant intake temperature, coolant output temperature or temperatures of individual cells), state of charge (SOC) or depth of discharge (DOD) to indicate the charge level of the battery and current in and/or out of the battery.
Some battery management systems include protection mechanisms configured to prevent the battery from operating outside of a predefined safe operating area. Battery protection mechanisms have become increasingly important, particularly as technology has advanced and many everyday consumer products rely on rechargeable batteries, such as, for example, lithium ion batteries, for power. If a lithium ion battery, for example, overcharges, strong exothermic reactions are possible and the potential for causing a fire increases, presenting a dangerous condition for the user.
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art.